Excessive use of nitrogen fertilizers causes overgrowth of plants, making crops too lush and prone to diseases, insect pests and other problems.
1. Plants grow too vigorously: Excessive nitrogen fertilizer will stimulate the growth of plant stems and leaves, causing the phenomenon of "over-vigorous growth". The plants will be huge in size but not high in yield, with reduced quality and reduced stress resistance.
2. Poor root development: Excessive nitrogen promotes the growth of stems and leaves, but inhibits root growth, resulting in "shallow horizontal roots", which is not conducive to the absorption of nutrients and water.
3. Excess nitrogen in plants: Excessive use of nitrogen fertilizers leads to the accumulation of a large amount of unmetabolized nitrogen and amino acids in the body, which affects the normal physiological metabolism of plants.
4. Decreased plant immunity: Excessive nitrogen can weaken the immunity of plants, making them prone to diseases such as cabbage soft rot, wheat rust, etc., and even affecting yield and quality.
5. Environmental pollution: Most of the excessively applied nitrogen fertilizer is lost through rainwater leakage, which not only wastes resources, but also causes soil acidification and groundwater pollution; the reduction of nitrogen into ammonia and other substances can also cause air pollution.
Therefore, when using nitrogen fertilizer, it is necessary to reasonably control the amount used according to different crops and soil conditions to avoid excessive use.